Denture adhesive compositions

ABSTRACT

A denture adhesive base composition consisting essentially of polyvinyl pyrrolidone and ethylene oxide polymer. A denture adhesive composition including this base composition is also provided with other optional adhesive components. Also is provided a method for formulating a novel denture adhesive base composition consisting essentially of polyvinyl pyrrolidone and ethylene oxide polymer.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention is directed to denture adhesives or stabilizers,and particularly to an improved denture adhesive composition.

2. Description of the Prior Art

Traditionally, dentures within the mouth were secured by using adherentpowders prepared from natural gum materials such as karaya, acacia ortragacanth gum. These materials have the property of swelling to manytimes their original volume upon the addition of water to form agelatinous or mucilaginous mass. Cream forms of the adherent, preparedfrom finely ground particles of the gums, were also available and usedinstead of the powder composition.

Over the years, there have been numerous improvements over theabove-described simple denture adhesive formulations. U.S. Pat. No.2,978,812 discloses a denture fixative composition which includes anethylene oxide polymer having a molecular weight between 50,000 and5,000,000 in an amount preferably comprising at least 50% of the activefixative material. GB Patent No. 1,444,485 discloses a fixing agentcomprising a solution of 4 to 44 wt. % of a polyvinyl pyrrolidone(“PVP”). U.S. Pat. No. 3,003,988 describes the use of mixed salts ofmore than 40 wt. % of a water-insoluble water-sensitized polymericmaterial consisting essentially of lower alkyl vinyl ether maleicanhydride polymers. U.S. Pat. No. 5,001,170 discloses a substantiallyanhydrous mixture of about 20 40 wt. % methyl vinyl ether maleic acidcopolymer, 20-40 wt. % of PVP, and 20-40 wt. % of ethylene oxidepolymer.

The use of ethylene oxide polymer, or polyethylene oxide (“PEO”), hasdeclined recently, being supplanted by metal crosslinked polymers whichexhibit greater strength. Recent improvements include the use of a loweralkyl vinyl ether maleic acid, anhydride, or salt polymer or mixturesthereof and one or more metallic salts selected from the groupconsisting of calcium, magnesium, strontium, sodium, potassium,zirconium, and zinc or mixtures thereof. U.S. Pat. No. 5,830,933discloses a denture adhesive composition with about 15-55 wt. % of asalt of a copolymer of maleic acid or anhydride.

Applicants have found that by simply complexing PEO chains to PVPmolecules surprisingly improve the cohesive strength of PEO, yieldingdenture adhesive formulations comparable to formulations based on saltsof polymaleic acid methyl vinyl ether in sensory tests as well ascohesive strength, without the need for metal crosslinked polymersystems.

SUMMARY OF THE INVENTION

A denture adhesive formulation consisting essentially of a dentureeffective amount of polyethylene oxide (“PEO”) and polyvinyl pyrrolidone(“PVP”). In one embodiment of the invention, the composition consistsessentially of from about 15 to 75 wt. % PVP and from about 5 to 40 wt.% PEO. In another embodiment, the composition consists essentially offrom about 20 to 70 wt. % PVP and 10 to 30 wt. % PEO.

The invention also relates to a method for adhering a denture to theoral mucosa resulting from the use of the new composition of the presentinvention.

DESCRIPTION OF THE DRAWING

FIGS. 1, 2 and 3 are graphs of adhesive force in lbs. vs. the hydrationtime in minutes, comparing the adhesive composition of the inventionwith comparative examples.

DETAILED DESCRIPTION OF THE INVENTION

Applicants have unexpectedly discovered a novel denture adhesivecomposition consisting essentially of two ingredients, polyvinylpyrrolidone and ethylene oxide polymer, without the need for methylvinyl ether maleic acid, anhydride, or salt polymers nor the processingstep for cross-linking these polymer systems with metal ions.

First component PVP Polyvinyl pyrrolidone, also named providone or PVP,is a known binding and suspending agent which is commercially available.The PVP polymer is typically a polymer of N-vinyl-2-pyrrolidone. In oneembodiment, the PVP polymer has a weight average molecular weight of20,000 to 1,500,000. In another embodiment, the PVP has a weight averagemolecular weight of 25,000 to 1,500,000, for example, of 25, 30 or 90 ofK-value. A commercially available PVP is from BASF under the tradenameKollidon, Mv ca. 1,100,000

Second component PEO The second component of the adhesive formulation ispoly(ethylene oxide) or PEO. PEOs are water soluble, non-ionic,polyether homopolymers having molecular weights from about 100,000 toabout 5,000,000. The homopolymers are white powders which when hydrateddevelop into a gelatinous mass having adhesive characteristics. Thepolyether polymers have the chemical structure—(CH2CH20)n—wherein nrepresents the degree of polymerization of the polymer and may have avalue from about 2,000 to about 100,000. PEOs of the type employed inthe present invention are more fully described in “Polyox,” 1978,published by Union Carbide Corporation, New York, N.Y., as TechnicalBulletin F-44029B. PEOs useful in the invention include linear, watersoluble polyethylene oxides as well as crosslinked PEOs. PEOs arecommercially available from Union Carbide Corporation under thetrademark Polyox.

The above two components are used in safe and adhesively effectiveamount, which herein means an amount sufficient to provide adherence tothe oral cavity. In general, the composition consists essentially offrom about 15 to 75 wt. % PVP and from about 5 to 40 wt. % polyethyleneoxide. In one embodiment, the denture adhesive composition consistsessentially of from about 20 to 50 wt. % PVP and 5 to 30 wt. %polyethylene oxide for a cream formulation. In one embodiment of adenture liner formulation, the composition consists essentially of fromabout 20 to 70 wt. % PVP and 5 to 20 wt. % polyethylene oxide

Optional adhesive components In addition to the two ingredients asindicated above to prepare the adhesive base, the composition mayoptionally contain other components to aid in enhancing the adhesivenature of the base components, including those commonly known and usedin the adhesive art.

The composition of the present invention is effective in adhering adenture to the oral mucosa without the need to include any methyl vinylether maleic acid, anhydride, or salt of the copolymers within. However,these ingredients and equivalents thereof may be included although it isnot necessary to do so.

Suitable optional adhesive components include the traditionalwater-soluble hydrophilic colloids or polymers having the property ofswelling upon exposure to moisture to form a mucilaginous mass. Thesematerials include copolymers of maleic acid or maleic anhydride or saltsthereof, natural gums, synthetic polymeric gums, synthetic polymers,mucoadhesive polymers, hydrophilic polymers, saccharide derivatives,cellulose derivatives, and mixtures thereof. Examples of such materialsinclude karaya gum, guar gum, gelatin, algin, sodium alginate,tragacanth, chitosan, acrylamide polymers, polyacrylic acid derivativessold under the trademark Carbopol®, polyvinyl alcohol, polyamines,polyquartemary compounds, polybutenes, silicones, cationicpolyacrylamide polymers.

In one embodiment, the optional adhesive components are cellulosederivatives in the form of a full or partial salt such asmethylcellulose, sodium carboxymethylcellulose, hydroxyethylcellulose,hydroxypropylcellulose, hydroxy-propylmethylcellulose,carboxy-methylcellulose. In another embodiment, the optional componentsare carboxy-methylcellulose, karaya gum, sodium alginate, chitosan,polyvinyl alcohol, and mixtures thereof. In general, the other adhesivecomponents may be present at a level of from about 0% to about 70%. Inone embodiment, they are from about 5% to about 50%. In anotherembodiment, they are from about 2% to about 20% by weight of thecomposition.

Optional ingredients and excipients In addition to the foregoingmaterials, the denture adhesive composition may be formulated withadditional components well-known in the denture adhesive art includingwaxes, oils, preservatives, flavoring agents, colorants, sweeteningagents, viscosity modifiers and so forth.

The waxes useful in the invention comprise both natural and syntheticwaxes and include without limitation animal waxes such as beeswax,lanolin and shellac wax, vegetable waxes such as carnauba, candelillaand bayberry wax, mineral wax such as petroleum waxes includingparaffin, and microcrystalline.

The oils useful in the invention include without limitation mineral oil,vegetable oil such as corn, soybean, cottonseed, castor, palm andcoconut oils and animal oil such as fish oil, and oleic acid.

Flavoring agents well known to the denture adhesive art may be added tothe compositions of the present invention. These flavoring agents may bechosen from synthetic flavor oils and/or oils derived from plants,leaves, flowers, fruits and so forth, and combinations thereof.Representative flavor oils include: spearmint oil, cinnamon oil, oil ofwintergreen (methylsalicylate) and peppermint oils. Also useful areartificial, natural or synthetic fruit flavors such as citrus oilincluding lemon, orange, grape, lime and grapefruit, and fruit essencesincluding apple, strawberry, cherry, pineapple and so forth. Theflavoring agent may be a liquid, spray dried, encapsulated, adsorbed ona carrier and mixtures thereof. A preferred flavoring agent ispeppermint oil. The amount of flavoring agent utilized may varydepending on such factors as flavor type, adhesive formulation andstrength desired. In general, amounts of about 0.01% to about 5.0% byweight of the total denture adhesive composition are usable. In oneembodiment of the invention, amounts of about 0.05% to 0. 15% are used.

Preservatives which may be used in the denture adhesive formulations ofthe invention include those known antimicrobial agents conventionallyemployed in the art, such as benzoic acid and sodium benzoate; theparabens; sorbic acid and sorbates; propionic acid and propionates;acetic acid and acetates; nitrates and nitrites; sulfur dioxide andsulfites; antibiotics; diethyl pyrocarbonate; epoxides; hydrogenperoxide; and phosphates. The parabens include the methyl, ethyl,propyl, and butyl esters of parahydroxybenzoic acid. Methyl paraben andpropyl paraben are the preferred preservatives of the invention,utilized in amounts of about 0.03% to about 0.6% by weight of the totaldenture adhesive composition.

The denture adhesive compositions may also include the use of sweetenerswell known in the art. The sweetening agent may be selected from a widerange of materials including water-soluble agents, water-solubleartificial sweeteners, and dipeptide based sweeteners, includingmixtures thereof. Representative sweeteners include: a) water-solublesweetening agents such as monosaccharides, disaccharides andpolysaccharides such as xylose, ribose, glucose, mannose, galactose,fructose, dextrose, sucrose, sugar, maltose, partially hydrolyzedstarch, or corn syrup solids and sugar alcohols such as sorbitol,xylitol, mannitol, maltitol, hydrogenated starch hydrolysate andmixtures thereof; and b) water-soluble artificial sweeteners such as thesoluble saccharin salts, i.e., sodium or calcium saccharin salts,cyclamate salts, acesulfam-K, sucralose and the like, and the free acidform of saccharin; and c) Dipeptide based sweeteners such asL-aspartyl-L-phenylalanine methyl ester and the like. In general, theamount of sweetener may be about 0.001% to about 5% by weight of thefinal denture adhesive composition.

The colorants useful in the present invention include the pigments suchas titanium dioxide, and may also include dyes suitable for food, drugand cosmetic applications. These colorants are known as F.D. & C. dyes.Illustrative examples include indigo dye, known as F.D. & C. Blue No. 2,which is the disodium salt of 5,5′-indigotindi-sulfonic acid; F.D. & C.Green No. 1, comprises a triphenylmethane dye and is the monosodium saltof the 4-[4-Nethyl-p-sulfobenzylamino)diphenylmethylene]-[1-(N-ethyl-N-P-sulfobenzyl)-2,5-cyclohexadienimini].A preferred colorant is F.D. & C. Red No. 3.

The viscosity modifiers useful herein include quaternary ammoniumcompounds and similar agents, starches, gums, casein, gelatin andsemisynthetic cellulose.

The composition of the present invention may also be used as a dentureadhesive and/or bioadhesive and comprise one or more therapeutic activessuitable for mucosal or topical administration. The phrase “suitable formucosal or topical administration,” as used herein, describes agentswhich are pharmacologically active when absorbed through internalmucosal surfaces of the body such as the oral cavity, or applied to thesurfaces of the skin. Therapeutic actives may be present at a level offrom about 0% to about 40% by weight of the composition.

Therapeutic actives that are useful in these compositions includeantimicrobial agents such as iodine, sulfonamides, bisbiguanides, orphenolics; antibiotics such as tetracycline, neomycin, kanamycin,metronidazole, or clindamycin; anti-inflammatory agents such as aspirin,acetaminophen, naproxen and its salts, ibuprofen, ketorolac,flurbiprofen, indomethacin, eugenol, or hydrocortisone; dentinaldesensitizing agents such as potassium nitrate, strontium chloride orsodium fluoride; anesthetic agents such as lidocaine or benzocaine;antifingals; aromatics such as camphor, eucalyptus oil, and aldehydederivatives such as benzaldehyde; insulin; steroids; andanti-neoplastics. It is recognized that in certain forms of therapy,combinations of these agents in the same delivery system may be usefulin order to obtain an optimal effect. Thus, for example, anantimicrobial and an anti-inflammatory agent may be combined in a singledelivery system to provide combined effectiveness.

Preparation The denture adhesive compositions may be in the form of apowder, a paste or cream form, or a liner form. The means for preparingsuch formulations is well known in the denture adhesive art, employingconventional types of mixing equipment for blending, heating, andcooling solids and liquids. In one embodiment, mixing is performed attemperatures suitable to melt the components, i.e., petrolatum, to beblended.

In the powder form, the components are admixed with flavoring agents andcolorants, together with other ingredients such as non-toxic anti-cakingagents (silica, magnesium stearate, talcum powder or the like). Themixture of ingredients is thoroughly agitated or stirred to yield agenerally homogenous intermixing of all components.

In the cream or paste formulation, the components are admixed withpetrolatum along with the previously described waxes, oils,preservatives, flavoring agents, colorants, sweetening agents, viscositymodifiers and so forth.

In the liner or layer form, the components are uniformly mixed and thencoated onto a non-adhesive self-supporting coating layer by anyconventional coating techniques, such as by spraying (if the material isliquid or slurry or dissolved or suspended in a liquid such as water) orby sifting (if the denture adhesive is in powder form). In anotherembodiment, the components are admixed with the previously describedwaxes, oils, preservatives, flavoring agents, colorants, sweeteningagents, viscosity modifiers and so forth. The liner is then formed byany of a variety of techniques known in the polymer film-forming art,including casting, calendaring, coating, and extrusion. In oneembodiment to form liners, the components are first mechanicallysoftened by a ring roller; smoothed on a hydraulic press; and die-cut asdesired into denture liner shapes or other desired shapes.

To further illustrate the invention, examples are set forth below. Inthese, as throughout the specification and claims, all parts andpercentages are by weight and all temperature in degree centigradesunless otherwise indicated.

EXAMPLES 1-3 Adhesive Force Evaluation

2 g. samples of each of the following prepared powder compositions wereevaluated for adhesion characteristics by adhesive force testing calledthe “Dislodge Force Method.” This test method involves the use of twoplates, an upper plate and a lower plate, in a water bath at about 37°C. The upper plate is lined with felt (representing the maxilla) andattached to a Chatillon® gauge and moving ram. The lower plate is madeout of polymethyl methacrylate (representing the denture) and attachedonto a hinge which is attached to a Chatillon® test stand. As the upperplate applies downward pressure, the lower plate swings downward ontothe hinge. This action simulates the biting motion of the mouth. Theswinging motion of the lower plate simulates the dislodgement of adenture.

In this test, four stripes of adhesive with about 0.125 grams ofadhesive per stripe are applied onto the lower plate. The two plates arethen brought together under 10 lbs. compression force for 5 minutes. Atthe end of the 5 minutes, compression is removed and the upper plate islowered at a rate of 25 mm per minute. A force (representing the firstdislodge force reading) is registered by the Chatillon® gauge. Duringthis cycle, the downward swinging motion of the lower plate representsdislodgment. This compression, decompression, and reading cycle isrepeated again for 11 more times, giving a total of 12 cycle readings of5 minutes each, or a total of 60 minutes hydration time. Recording(dislodge force in lbs.) for the 1st, 2nd, 3rd, . . . , 12th cycle wererecorded and then plotted graphically in the Figures.

Comparative Comparative Present invention Components Example 1 Example 2Example 3 Polyvinyl pyrrolidone — 40 30 K90 Polyox 301 100 mesh 40 — 10CMC 7H3SXF 10 10 10 Petrolatum 50 50 50

FIG. 1 compares the PVP / Polyox composition of the present invention(Example 3) with Comparative Examples 1 (with Polyox) and 2 (with PVP).FIG. 2 compares the composition of the present invention (Example 3)with a commercially available denture adhesive composition, Polygrip®comprising metal salts of methyl vinyl ether/maleic acid or anhydridecopolymers or Gantrez®. FIG. 3 compares the PVP / Polyox composition ofthe present invention (Example 3) with a commercially available dentureadhesive composition, Fixodent®, also known to contain metal salts ofmethyl vinyl ether/maleic acid or anhydride copolymers or Gantrez®.

EXAMPLE 4 Cream Formulation

In this example, the PVP and Polyox powders are mixed together and addedto the melted petrolatum, mineral oil, and Carbopol® in a KitchenAidmixer with stirring. The flavors and dyes are added and intimately mixedin for about 30 minutes. The resultant denture adhesive composition is aviscous material which turns into a smooth soft mass upon wetting andmixing with water or saliva.

Polyvinyl pyrrolidone K90 30.00 Polyox 301 100 mesh 10.00 CMC 7H3SXF10.00 Mineral Oil 18.55 Petrolatum 29.00 Carbopol ® 981NF 1.00 Silicondioxide 1.00 SD peppermint flavor 0.20 SD spearmint flavor 0.20 D&C Red#7 0.02 D&C Red #30 0.03 Total 100.00

EXAMPLE 5 Denture Liner Formulation

For this formulation, polyethylene oxide powder is first admixed withPVP in a kitchen aid mixer and then added to a mixture of Carbopol® andmethyl cellulose. The blend is dissolved with an appropriate amount ofwater and extruded forming a film. A typical denture liner formulationis as follows:

Kollidon PVP K90 58.00 Polyox 301 100 mesh 10.00 CMC 7H3SXF 10.00Carbopol ® 981NF 1.00 Deionized water 30.00 Total 100.00

EXAMPLE 6 Sensory Evaluation

The denture cream formulation in example 4 was tested againstcommercially available denture adhesive cream formulations containingmetallic crosslinked methyl vinyl ether maleic acid copolymer. Thesensory tests were carried out to evaluate the organolepticcharacteristics of the polyethylene oxide / polyvinyl pyrrolidoneformulation of the present invention against leading market dentureadhesives.

In organoleptic evaluation tests, several expert evaluation panels oftwenty-five panelists total were presented with two samples of dentureadhesive creams. One was the formulation of the present invention, theother was the commercial formulation. The panelists were asked tofill-out a questionnaire to evaluate the denture creams based on fifteendifferent criteria, e.g., mouth feel, hold property, time hold propertydevelops, etc. Statistical analyses of the tests indicate that thedenture formulation of the present invention was judged to providedenture stabilizing properties comparable to commercial formulationscomprising metal salts of methyl vinyl ether/maleic acid or anhydridecopolymers or Gantrez®. It was also found that the denture formulationof the present invention did not exhibit any objectionable phaseseparation or oozing from a dental plate.

Applicants intend to cover, in the appended claims, modifications thatare within the scope of the present invention.

What is claimed:
 1. A denture adhesive base composition consistingessentially of: a) from about 15 to 75 wt. % polyvinyl pyrrolidone andb) from about 5 to 40 wt. % ethylene oxide polymer.
 2. The dentureadhesive base composition of claim 1, wherein said polyvinyl pyrrolidoneis about 20 to 70 wt. %, and said ethylene oxide polymer is about 5 to20 wt. %, based on the total weight of the denture adhesive basecomposition.
 3. The denture adhesive base composition of claim 2,wherein said polyvinyl pyrrolidone is about 40 to 70 wt. %, and saidethylene oxide polymer is about 5 to 20 wt. %, based on the total weightof the denture adhesive base composition.
 4. The denture adhesive basecomposition of claim 2, wherein said polyvinyl pyrrolidone is about 20to 50 wt. %, and said ethylene oxide polymer is about 5 to 20 wt. %,based on the total weight of the denture adhesive base composition. 5.The denture adhesive base composition of claim 3, wherein said polyvinylpyrrolidone is present in amounts of from about 25 to 40 wt. %, and saidethylene oxide polymer is present in amounts of from about 5 to 20 wt.%, based on the total weight of the denture adhesive base composition.6. The denture adhesive composition of claim 1 in the form of a creamformulation.
 7. The denture adhesive composition of claim 1 in the formof a denture liner.
 8. The denture adhesive composition of claim 1,further including from about 0 to about 70 percent by weight, based onthe total weight of the denture adhesive composition, of additionalmaterials selected from the group consisting of: cellulose derivatives,polyacrylic acid derivatives, sodium alginate and mixtures thereof. 9.The denture adhesive composition of claim 8, further including fromabout 0 to less than 20 percent by weight, based on the total weight ofthe denture adhesive composition, of a lower alkyl vinyl ether maleicacid, anhydride, or salt polymer or mixtures.
 10. The denture adhesivecomposition of claim 8, wherein the cellulose derivatives comprisescarboxymethyl cellulose.
 11. The denture adhesive composition of claim9, further including additional materials selected from the groupconsisting of waxes, oils, preservatives, flavoring agents, colorants,sweetening agents, viscosity modifiers and mixtures thereof.
 12. Thedenture adhesive base composition of claim 9, further includingnon-toxic, powdered, excipient materials.
 13. A method for preparing adenture adhesive composition comprising: a. preparing a substantiallyanhydrous mixture consisting essentially of from about 15 to 75 wt. %polyvinyl pyrrolidone and from about 5 to 40 wt. % ethylene oxidepolymer; b. forming a denture adhesive composition including saiddenture adhesive base composition; and c. recovering said dentureadhesive composition.
 14. The method of claim 13, wherein said dentureadhesive composition further includes up to about 70 percent by weight,based on the total weight of the denture adhesive composition, ofadditional materials selected from the group consisting of: cellulosederivatives, polyacrylic acid derivatives, sodium alginate and mixturesthereof.
 15. The method of claim 14, wherein said cellulose derivativescomprise carboxymethyl cellulose.
 16. The method of claim 14, whereinsaid denture adhesive composition further including additional materialsselected from the group consisting of waxes, oils, preservatives,flavoring agents, colorants, sweetening agents, viscosity modifiers andmixtures thereof.
 17. A process for the preparation of the dentureadhesive composition of claim 1, wherein the denture adhesivecomposition is mechanically softened and pressed smooth and cut intodenture shapes.
 18. A denture stabilizing composition consistingessentially of a safe and adhesively effective amount of two components:a) polyvinyl pyrrolidone and b) ethylene oxide polymer.
 19. The dentureadhesive composition of claim 18, further including from about 0 toabout 70 % by weight, based on the total weight of the denture adhesivecomposition, of additional materials selected from the group consistingof: cellulose derivatives, polyacrylic acid derivatives, sodium alginateand mixtures thereof.
 20. The denture adhesive composition of claim 19,further including from about 0 to less than 20% by weight, based on thetotal weight of the denture adhesive composition, of a lower alkyl vinylether maleic acid, anhydride, or salt polymer or mixtures.